1. Field of the Invention
This invention relates to earth working implements useful for physically treating the earth and more particularly to row-crop cultivating implements having a plurality of earth working elements in tandem and double tandem relationship, said elements having a rotating or orbital motion due to the resistance of the earth to movement of the elements thereover. This invention further relates to cultivating implements wherein the rolling or rotating earth working element is a generally circular, plate-like member and there are a plurality of groups or clusters of said members, each group or cluster comprising a subassembly of parts which is handled as a unit. This invention still further relates to means, used in conjunction with an earth working element of a cultivator disc subassembly, for limiting the lateral movement of material thrown out by the disc earth working elements, said means also having a rotating movement imparted thereto by rolling contact with the ground.
2. Description of the Prior Art
Disc earth working implements having forward and rear pairs of disc gangs which are angularly adjustable relative to the longitudinal axis of the implement for varying the cultivation pattern are generally known. They employ as earth working elements generally concave-shaped disc bodies which serve to produce furrows in the ground during operation. By varying the angular relationship between the respective pairs of forward and rear disc clusters or gangs, the ground area disced and the width and depth of each furrow can be controlled. The forward disc clusters are usually supported so that the concave surfaces of the disc blades are directed outwardly from the longitudinal axis of the implement with a resulting movement of dirt outwardly from the longitudinal axis of the implement during operation. The rear disc clusters are usually supported so that the concave surfaces of the disc blades are directed inwardly toward the longitudinal axis of the implement with a resulting movement of dirt inwardly toward the longitudinal axis of the implement during operation. The net effect of this arrangement is to shift the soil to and fro and to reduce the tendency of the implement to drift sidewise during operation.
Such earth working implements have been employed for a variety of agricultural purposes such as harrowing and plowing open fields and cultivating row crops. The use dictates the physical treatment of the soil needed and hence the design of the implement. For example, when used for cultivating row crops, the implement will often have a means to limit the lateral movement of earth thrown out by the respective disc clusters to protect adjacent rows of plants. See U.S. Pat. Nos. 1,117,728 (shows rotating "fender discs" associated with cultivator disc assemblies) and 2,635,520 (shows "dirt boards" associated with cultivator disc assemblies). However, the need for and the extent of "shielding" provided by such means is further governed by the specific row crop to be cultivated by the implement. Soybeans and beets require extensive shielding. Corn does not require shielding and in fact could be damaged if such shielding were provided.
Cultivation is a multipurpose agricultural operation broadly concerned with conditioning the soil to improve water retention characteristics, with weed control, and with conditioning the soil to maximize the yield of the row crop being cultivated. An example of the latter purpose is "hilling" of corn, referred to above.
The cultivation of sugar cane has peculiar needs with which the present invention is concerned. The roots of the sugar cane plant are very slender and almost cylindrical. The roots are seldom more than a foot in length and have a few short fibers at their extremities. Exposure of these roots to the atmosphere is fatal to the plant. However, equally undesirable is excessive build up of soil on or near the plants during cultivation. Present cultivator apparatus used by sugar-cane growers are usually of the driven, roto-tiller type. This type of machine is plagued by high maintenance costs. The lack of success of present cultivation methods and apparatus is further apparent from the recent development of so-caled "minimal cultivation" methods in the sugar cane industry as a result of the discovery that cultivation--an operation intended to increase cane production--often has the opposite effect, particularly when the cane is cultivated periodically through the growing season.
Accordingly, a principal object of the present invention is to provide a sugarcane cultivator of the disc type, the use of which will have the desired result of maximizing cane production.
Another object of this invention is to provide an earth working implement for hitched attachment to a tow vehicle, the implement comprising a trailer with retractable wheels for transportation, with at least six pluralities of adjustable cultivator disc assemblies arranged in double tandem relationship to one another, and an adjustable soil deflector disc associated with the two forward pairs of adjustable cultivator disc assemblies.
Another object of the present invention is to provide means to permit individual adjustment of the angular relationship of each plurality of cultivator discs and associated deflector disc relative to the longitudinal axis of the trailer as well as means to permit individual adjustment of the lateral spacing between each plurality of cultivator discs and associated deflector disc relative to said longitudinal axis.
A further object of the invention is to provide means to permit the angular and vertical adjustment of each deflector disc relative to its associated plurality of cultivator discs.
A still further object of the invention is to provide an earth working implement with exceptional directional stability.
Yet another object of the invention is to provide means to permit the attachment of additional pluralities of adjustable cultivator discs as well as rakes to the trailer.